Process of treating refractory complex ores of gold and silver.



UNITED STATES Patented. September 22, 1903? v PATENT. ()FFICE.

CHARLES E. BAKER AND ARTHUR W. BURWELL, OF CLEVELAND, OHIO.

PROCESS OF TREATING REFRACTORY CDMPLEX ORES OF GOLD AND SILVER.

QPECIFICATI EON forming part of Letters Patent. No. 739,374, dated September 22, 1903.

Application filed Novemberll, 1902. Serial No. 130,843. (No specimens.)

. Ores of Gold and Silver, of which the follow-' ing is a specification.

This process is especially intended for the treatment of ores of gold and silver containing base metals, such as iron, copper, zinc, or

lead, combined with a metalloid. It is especially intended for the treatment of ores in which the metalloid will combine with chlo-.

rin to form a volatile chlorid, such as sulfids, arsenids, antimonids, and selenids.

The process, generally stated, consists in treating raw crushed oreor concentrates with chlorin while subjected to a temperature suf: ficient to cause the chlorin 'to'combine with the metalloid to produce a volatile chlorid, which is'driven OE and may becondensed. The base metals present also combine with chlorin to form soluble protochlorids. The gold is liberated in a free state and the silver is converted into a chlorid. To obtain the best results, both the ore and chlorin should be dry and the ore should be agitated to increase the speed of the reaction. The residue left after the metalloid is driven off is then treated with water, whereby the base-metal chlorids are brought into solution, while the free gold and silver chlorid remain with the gangue and may be separately recovered.

Theprocess may be carried out by the use of any suitable apparatus. One which has been employed is shown in the accompanying drawing, in which the figure is a vertical longitudinal section showing the ore-drum in elevation.

The apparatus shown comprises a revolving drum 1, preferably of boiler-iron lined with'porcelain. Thisdrum has hollow trunnions 2 3, also lined with porcelain, which are supported in journal-boxes 4:, carried by standards 5. A gear-wheel 6 for rotating the drum is secured on trunnion 3. The drum has a suitable opening 7 for receiving and discharging its contents. Surrounding the drum is a chamber 8, which may be of boileriron 9 with a covering 10 of asbestos. A fine 11 opens into chamber 8 at one end and nearits base, serving for the introduction of heatinggases.

pose of charging and discharging'it.

A flue 12 for discharging-the waste gases leads from the other end of the chamber near its top. A door 13in one side of the chamber gives access to the drum for the pur- For the sake of illustration the process will be described as carried out on an ore containing gold, silver, and iron combined with sulfur. The ore is crushed toabout fifty mesh and a sufficient amount is placed in the drum to one-third fill it. The drum is now set in rotation and its contents heated to about 150 centigrade, preferably by waste products of combustion introduced through fiue'll.. Dry

chlorin" gas is then introduced through trunnion 2 and combines with the sulfur to form sulfur chlorid, (8 01 This chlorid, however,volatilizes at a temperature of 138 centigrade, and is therefore driven off as rapidly as formed, escaping through trunnion 3, whence ,it is delivered to a suitable condenser and liquefied. The iron or other base metal in the ore is thus converted into a protochlorid,

and care must be taken to discontinue the introduction of chlorin gas at the precise moment when all of the sulfur has been removed,

which'can be determined by the fact that chlorin only then escapes through trunnion 3. This is necessary to prevent conversion of the ferrous chlorid into the more volatile ferric chlorid, which might be driven off with the sulfur chlorid. The residual mass is now treated with water, either in the drum or in a separate vessel,whereby the iron or other basemetal chlorid is brought into solution, while the gold and silver remain in the gangue, the

The ferrous chlorid solution is The process is substantially the same when applied to arsenids, antimonids, 850., a suitable temperatn re being employed to effect the production and volatilization of the metalloid chlorid without volatilizing the base-metal chlorid.

We elain1- 1. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid with chlorin, and vaporizing and separating the metalloid chlorid from the base metals in the ore, as set forth.

2. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid, base metal and silver, if present, with chlorin, and vaporizing and separating the metalloid chlorid from the base metals in the ore, as set forth.

3. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid with chlorin by bringing chlorin into contact with the orewhile hot, and vaporizing and separating the metalloid chlorid from the base metals in the ore, as set forth.

4. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid, base metal and silver, if present, with chlorin by bringing chlorin into contact with the ore while hot, and vaporizing and separating the metalloid chlorid from the base metals in the ore, as set forth.

5. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid with chlorin by bringing dry chlorin into contact with the dry ore while hot, and vaporizing and separating the metalloid chlorid from the base metals in the ore, as set forth.

6. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid, base metal and silver, if present, with chlorin by bringing dry chlorin into contact with the dry ore while hot, and vaporizing and separating the metalloid chlorid from the base metals in the ore, as set forth.

7. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid, base metal and silver, if present, with chlorin, vaporizing and separating the metalloid chlorid from the base metals in the ore, and dissolving and removing the basemetal chlorid, as set forth.

8. The process of treating ores of gold and silver containing a base metal or metals and a metalloid, which consists of combining the metalloid, base metal and silver, if present, with chlorin, vaporizing and separating the metalloid chlorid from the base metals in the ore, dissolving and removing the base-metal with chlorin, vaporizing and separating the metalloid chlorid from the base metals in the ore, dissolving and removing the base-metal chlorid, and separately recovering the gold and silver, as set forth.

10. The process of treating ores containing a base metal or metals and a metalloid, which consists of combining the metalloid with chlorin, and vaporizing and separating the metalloid chlorid from the base metals, as setforth.

11. The process of treating ores containing a base metal or metals and a metalloid, which consists of combining the base metal and metalloid with chlorin by bringing dry chlorin into contact with the dry ore while hot, and vaporizing and separating the metalloid chlorid from the base metal chlorid, as set forth.

In testimony whereof we affix our signatures in presence of two witnesses.

CHARLES E. BAKER. ARTHUR \V. BURWELL. \Vitnesses:

A. G. BOWEN, S. E. STONE. 

